My first thought is wow you are super super stressed. My second thought, get thyself to a counselor who specializes in dealing with families in addiction....now. I am so so sorry for all you are going through, my heart just hurts for you.
If she works a job, I would say to tell her if she is going to stay with you she has to put every extra penny into building a fund to be able to move out on her own, even if it is just renting a room somewhere. Make it clear the ultimate goal is for her to move out. You cannot carry on this way.
It's sort of like the airmask on a plane. You put it on yourself first or you are not able to help anyone else.
Keep coming to SR, there is great support here.